Harrow.



J. n. MQMILLAN. I

HABROW.

APPLICATION FILED In. 21, 1908.

Patented Oct. 6, 1908.

"I: NORRIS rs'rlks cm. vIAsulNamN, n. c.

Jonu D. MM1LLAN, OF ALHAMBRA, CALIFORNIA.

. HARROW.

To all whom it may concern: g

Be it known that I, J 01m D. f

a citizen of the United Alhambra, in the county State of California, newand. useful Improvements? in Harrows,

States, residing at of Los Angeles and of which the following is aspecification.

This invention relates to spring tooth harrows, and the principal objectof said inventlon is to provide reliable and efficient means for quicklyadjusting the throw of the lever which controls the depth of penetrationofthe spring teeth of theharrow'.

Spring-tooth harrows as at present constructed, are provided-with alever for rocking the tooth-bars togive the teeth the requiredpenetration and to raise them out of the ground when the harrow is beingdrawn to and from the ffield of operation. This lever is rigidly, boltedto a yoke or casting connected to the tooth-bars by a bolt, and a sectorrack is provided for holding the lever in place when it is thrown intothe required position. The throw of this lever is thus limitedin itsmovement relatively to the sector rack, and this throw of the lever issuflicient when the harrow is new and the teeth have not becomeshortened or. worn away. There-being no means of adjustment of thislever relatively to the toothbars, when the teeth become worn, theentire harrow must be readjusted, and this is an expensive operation.

My invention embodies simple and inexpensive means for connecting thetooth-bars I to the lever in such manner that the toothbars may beeasilyand quickly shifted relatively to throw of lever. In its broadestaspect my invention involves novel, means for adjusting the regulatinglever of a spring-tooth harrow relatively'to the toothbars to compensatefor the wear of the teeth.

The objects and advantages referred. to may be attained by means oftheconstruction illustrated in the accompanying draw ing in which, r,

Figure l is a side elevation of a springtooth harrow embodying myimprove ments-Fig. 2 is a detail side view of my invention shownattached to a tooth-banand connected by linkdto thelower end of theregulating lever, the tooth-bar being shown in section-Fig. 3 is a viewtaken at right angles to Fig. 2.

d I Specification of Letters Patent. 1 Application filed March 21, 1908.Serial No. 422,502.

have invented certain 1 holes for the bolts Eatented Oct. 6, 1908.

ing rod, and 6'and d are the links which connect the tooth-bars to theconnecting rod.

These. parts may be of the usual or any suitable construction. a

As usually constructed the links 6 and d are connected at their lowerends to a yoke or a casting bolted to the tooth-bars-but not adjustably.

In accordance with my invention, the links 6 are connected by means ofbolts 7 and 8 to an adjusting device 1 A, forming my invention, andcomprising a yoke a, which partially surrounds the tooth-bar 9 and whichis firmly connected thereto by means of the bolts 10.

' Theadjusting device A is provided with a wide flat lug provided withbolt holes 'throughwhichthe bolts 7 and 8 pass, and

additional adjustingholes, b and c for the links 6.

The regulating lever, B, is integral with link ohwhich has a flattenedangularly bent end pivoted to the connecting rod 5. The lower end of thelink cl is provided with bolt 9 and h. The adjusting device A for thelever B is identical in construction with those to which the links 6 areconnected, and is provided with adjusting holes I) and c.

A sector rack 11 is secured to the connecting rod 5, and the spring pawl12 engages the teeth of said rack to hold the spring teeth 4 in therequired adjustment.

When the ends of the teeth 4: have been worn'awayby constant use, thelinks 6 and (Z to which the lever B is bolted may be adjusted asfollows: The bolts 8 are removed and. the bolts 7 loosened to serve aspivotal points between the links 6 and the adjusting device A. The bolts'8 are then passed through the same hole in the links and through holesI) or c in the adjusting device. The link (2 is adjusted in a similarmanner, as will be understood.

. From the foregoing it will be obvious that my invention provides for aquick adjustment to compensate for the wear of the teeth; that the costof the adjusting device is but slightly greater than the yoke or castingnection to a tooth-bar, and :1 lug having nd- 10 justing holes for thelinks.

In testimony whereof I afiix my signature, in presence of two witnesses.

JOHN D. MGMILLAN.

Vitnesses R. B. VALLACE, HENRY J. LINDEMAN.

